A 5-yrs-old girl presents with a several day history of localized swelling in the right side of her neck. There is no recent history of sore throat. Physical examination finds a low-grade fever, and one very tender, firm, slightly enlarged lymph node is palpated in the right cervical region. A CBC reveals a mild leukocytosis. A fine needle aspiration of the lymph node reveals scattered neutrophils. Which of the following is the most likely diagnosis?

Lymph nodes may be enlarged (lymphadenopathy) secondary to reactive processes, which can be eitheracute or chronic. Acute reaction (acute non specific lymphadenitis) can result in focal or generalized lymphadenopathy Focal lymph node enlargement is usually the result of bacterial infection (bacterial lymphadenitis). Sections from involved lymph nodes reveal infiltration by neutrophils. In contrast, generalized acute lymphadenopathy is usually the result of viral infections and usually produces a proliferation of reactive T lymphocytes called I immunoblasts. These reactive T cells tend to have prominent nucleoli and can be easily mistaken for malignant lymphocytes or malignant Hodgkin cells.